(57) A CCD comprises a two dimensional array of charge collection sites arranged in rows
and columns, each row being associated with a plurality of electrodes such as polysilicon
electrodes R1/, R1/2, R1/3 extending in the direction of the row, each electrode corresponding
to a respective voltage phase IΦ1 to IΦ3. The resistivity of the polysilicon electrodes
causes a time constant problem for the phase voltages when they appear at the central
regions of the electrodes and, for this reason, it has been proposed to run a conducting
strip along each polysilicon electrode to reduce its resistance (in a back-illuminated
device, the strips would not obscure the incoming radiation). However, it is difficult
to fabricate fine metal features, and this then places a restriction on how closely
the rows can be spaced. According to the invention, conducting strips are provided
which have repeatedly reversing portions inclined relative to the rows and in electrical
contact with the electrodes of a corresponding voltage phase of several rows. Preferably,
the conducting strips are zig-zag in shape to make multiple connections to each electrode
to which it supplies the respective phase voltage.
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